Electronic system, components and method for tracking files

ABSTRACT

A file tracking system including a processor, which maintains and interfaces with a database, a plurality of file folder retainers, and a plurality of file folders. The file tracking system actively maintains and updates the database, which includes file information, file location, and unique file address for the plurality of files, by providing interactive communication between the processor, the folder retainers, and the file folders. Each file folder may include an indicator light, such as an LED, which a user may cause to blink when trying to locate the file folder at a location accessed from the database.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.08/379,944 filed on Jan. 27, 1995, entitled U.S. Pat. No. 5,751,221,entitled ELECTRONIC SYSTEM, COMPONENTS AND METHOD FOR TRACKING FILES,the entire disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

In general, the present invention relates to an electronic system,hardware, and method for tracking the location of files and theircontainers. More specifically, the present invention relates to anelectronic file tracking system that maintains a database identifyingeach file and its current location by interactive communication betweena computer processor and the file folders. The invention is particularlyadapted for use with office furniture.

In a typical office environment, files are normally stored in variousfile cabinets located throughout the office. Each file cabinet or groupof file cabinets stores files belonging to a particular category. Thesefiles are typically organized in an alphabetical or numerical orderwithin the drawers of the file cabinet or group of file cabinets. Filesmay also be stored on or in various shelving units, trays, boxes, worksurfaces, bins, compartments, tables, desk drawers, or carts. In orderto make these files accessible to all office personnel, the files mustbe stored in an organized manner. Office personnel expend a substantialamount of time retrieving files, replacing files back into the filecabinets, and maintaining the organization of the files.

When someone wishes to obtain a particular file, he or she mustdetermine in which office, which file cabinet, and which drawer of thefile cabinet the file is supposed to be located. If the person lookingfor the file does not know the location of the file first hand, he orshe must make inquiries to the other employees or check a manuallymaintained listing of the file organization to locate the file. Oncethis person identifies where the file is supposed to be located, theperson must search through the numerous files stored in the drawer todetermine if the file is actually located in the drawer. In searchingthrough the file cabinet drawer, this person may discover that the fileis not located where it was supposed to be. The person must then againinquire about the office to determine if someone else has the file and,if no one else has the file, this person must search through other filedrawers to determine if the file is misfiled or lost. Active files tendto become stacked on the desktops of the employees most recently usingthose particular files, leading to poor accessibility for others.Clearly, tracking down a file may consume a significant portion of anemployee's time and any time spent looking for or reorganizing files isan inefficient use of that employee's time.

To maintain an organized system, when someone must add a number of newfiles to a particular drawer of a file cabinet that is already filled tocapacity, he or she must shift those files in the back of the drawer toanother drawer, which may also be filled to capacity. Further, whenevera sequential ordering scheme is used to organize files, even frequentlyaccessed files may be dispersed throughout a number of drawers ratherthan in the front of a single file drawer where the frequently accessedfiles would be more easily accessible.

The above problems are particularly prevalent in hospitals, doctor'soffices, law offices, government agencies, and anywhere else where largeamounts of printed documents or other media are handled and maintained.

One approach that was developed to alleviate some of the above problemsin tracking files is to provide a bar code label on each file folder andto maintain a database correlating the bar code I.D. of the file and itsrelative location. In order to accurately maintain the file locations inthe database, bar code readers are placed about the office for employeesto scan the bar code and enter a new location whenever the employeesmove a file from one location to another.

The problem with this approach is its reliance upon the employees totake the time to scan the bar code and enter user and locationidentification information into the database every time an employeepulls a file out of a file drawer or off a shelf. Furthermore, thedatabase may only identify the general location of the file, which maybe a location where many other files are also located. Thus, althoughsomeone looking for a file may know its general location, this personmay spend considerable time trying to locate the file amongst thenumerous other files, particularly if the file is misfiled.Additionally, not all possible locations and potential users of thefiles may be identified within the database. Thus, the database may notaccurately reflect the exact location of a file.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made to overcome the aboveproblems of the conventional filing system. The file tracking system ofthe present invention automatically determines when a file has beenremoved from its previous location, when it is returned, and determineswhen a new file has been added to the system. Additionally, the filetracking system of the present invention allows users to easily andaccurately identify the exact location of a file by having a processorcommunicate with a device carried by the file folders and activate anindicator, such as a light, on the file folders and/or file cabinets inresponse to a signal sent by the processor. Thus, the present inventionrequires minimal human interaction to maintain an accurate databaseidentifying the location of the files while permitting both random andordered filing of the file folders. Moreover, the file tracking systemof the present invention may be inexpensively and readily implemented inexisting office furniture.

Additional features and advantages of the invention will be set forth inpart in the description which follows and in part will be apparent fromthe description, or may be learned by practice of the invention.

The features and advantages of the invention may be realized andobtained by means of the instrumentalities and combinations particularlypointed out in the written description and claims hereof as well as theappended drawings.

To achieve these and other advantages, and in accordance with thepurpose of the invention as embodied and broadly described herein, thefile tracking system of this invention includes a database formaintaining at least file identity, file location, and unique fileaddress for a plurality of files, a processor for interfacing with thedatabase and issuing control signals, a bus connected to the processor,a folder retainer connected to the processor by the bus, a plurality offile folders, each file folder including an addressable device adaptedto be electrically connected to the bus when the file folder is placedin the folder retainer. Each folder may include an indicator which isactivated when the addressable device receives a control signal from theprocessor including the unique address corresponding to the file folder.The database may additionally store the following: access information,which may be used to prevent individuals from accessing certain filefolders; retention information, which may be used to determine thelength of time since the file folder was last accessed in order todetermine whether the file may be purged; classification information,which may indicate any classification groups the file folder isassociated with; access history, which may indicate who checked out thefile folder and when the file folder was checked in or out; key wordlists, which list certain key words that describe or may be found in thefile; and location history information, which may indicate the locationsand dates at which the file folder has been located over a period oftime.

The above features and advantages may also be attained by using the filecabinet of the present invention in a file tracking system. The filecabinet of the present invention includes a plurality of file drawers,at least one file drawer including a first conductor for providingcontrol signals a file folder when the file folder is placed in the filedrawer, the control signals being provided by the file tracking system,and a second conductor for providing a return path from the file folderplaced in the file drawer.

Additionally, the advantages of the present invention may be attained byusing a file folder of the present invention in a file tracking system.The file folder of the present invention includes at least one surface,an addressable device carried by the file folder and having a uniqueaddress, a first conductor on the surface electrically coupled to theaddressable device for providing control signals to the addressabledevice when the file folder is placed in a folder retainer, the firstconductor adapted to communicatively couple to a processor of the filetracking system, the control signals being provided by the processor,and a second conductor on the surface for providing a return path fromthe addressable device.

These and other features, objects, and benefits of the invention will berecognized by those who practice the invention and by those skilled inthe art, from the specification, the claims, and the drawing figures.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a pictorial view of a file tracking system constructed inaccordance with a first embodiment of the present invention;

FIG. 2 is a block diagram illustrating the hierarchy of the filetracking system of the present invention;

FIG. 3 is an electrical schematic view illustrating the electricalconnections of a portion of the file tracking system shown in FIG. 1;

FIG. 4 is an electrical schematic view of an addressable switch whichmay be used in the file tracking system of the present invention;

FIG. 5 is a perspective view of a file folder in electrical contact witha bus conductor according to a first implementation in the file trackingsystem of the present invention;

FIG. 6 is a perspective view of a file folder and a bus conductoraccording to a second implementation in the file tracking system of thepresent invention;

FIG. 7 is a perspective view of a hanging file folder in electricalcontact with a bus conductor according to a third implementation in thefile tracking system of the present invention;

FIG. 8 is a graphic view of a main user interface window of the filetracking system of the present invention;

FIG. 9 is a graphic representation of a debug window of the filetracking system of the present invention;

FIG. 10 is a graphic representation of a Get Number dialog box of thefile tracking system of the present invention;

FIG. 11 is a flow chart illustrating the polling operation of the filetracking system of the present invention;

FIG. 12 is flow chart showing the device scanning operation of asubroutine executed by the file tracking system of the presentinvention;

FIG. 13 is a flow chart showing the indicator light scanning operationof the file tracking system of the present invention;

FIG. 14 is a pictorial view of a file tracking system constructed inaccordance with a second embodiment of the present invention; and

FIG. 15 is a pictorial view of a file tracking system constructed inaccordance with a third embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the present preferredembodiments of the invention, examples of which are illustrated in theaccompanying drawings.

The exemplary embodiment of the file tracking system of the presentinvention is shown in FIG. 1 and is designated generally by thereference numeral 10. As used throughout this description of theinvention and in the following claims the term “media” includes paper,film, X-ray film, magazines, books, photographs, microfiche, video andaudio tapes, models, exhibits, or anything else retained and filed. Theterm “file folders” refers to any type of structure for containing mediaincluding bi-fold, side-tab, expandable, and tri-fold file folders, andmay further include various types of binders, jackets, envelopes, boxes,holders, cartons or the like. The term “files” as used herein includesthe file folder and all media inside. The term “folder retainers” refersto various numbers of, and/or combinations of, file trays, filecabinets, shelving units, desks, furniture drawers, packing boxes,archive tubs, wall-mounted or countertop file racks, bins, carts, pads,mats, desk tops, countertops, any work surface on which file folders arecommonly stacked or placed, or any other structure for holding filefolders. A “file locating device” broadly includes any device that wouldassist a user to locate a file. An “annunciator” is a file locatingdevice that audibly and/or visually announces the location of a file,and includes audible alarms, such as beepers, and visual indicators,such as light emitting diodes (LEDs). Additionally, other types ofannunciators or, as more broadly defined herein, file locating devices,such as an audible alarm, may supplement or replace the visual indicatorlights used in the file tracking system.

In general, file tracking system 10 includes a processor 20 and aplurality of folder retainers. For purposes of example, FIG. 1 shows afile tray 40, a file cabinet 50, a shelving unit 60, and a desk 85although any of the above defined folder retainers may be used invarious numbers and combinations.

A bus 30 communicatively couples processor 20 with the folder retainers.Each folder retainer includes bus conductors 80 for electricallycontacting one or more file folders 70. Bus 30 preferably includes twolines. One for providing control signals to file folders 70 and anotherfor providing a return. Although the preferred embodiment utilizes twolines, bus 30 may be implemented in any bus using any number of physicalor virtual, multiplexed lines. Bus conductors 80 may be included on asurface of a file retainer such as a file drawer, or embedded within aworking surface, such as a desktop, countertop, shelf, or tray, tocreate a file retainer location thereon.

Processor 20 includes a display 22 and an input device 25, such as akeyboard. Preferably, processor 20 is a personal computer. As will beexplained in greater detail below, processor 20 maintains and interfaceswith a database under the direction of an operating program thatinstructs processor 20 to actively communicate with the folder retainersand the file folders 70 via bus 30. In this manner, processor 20 mayupdate the database and maintain accurate information on the location offile folders 70 placed in the system. The database used may be anycommercially available ANSI SQL compatible database, such as MicrosoftAccess™ database.

A tray 40, which is useful in the file tracking system 10 of the presentinvention, may be formed of a conventional file tray modified to includea bus conductor 80 having at least two conductive strips (42, 43), anindicator light 45, such as a light emitting diode (LED), and anaddressable switch 100 (FIG. 4), which is connected between theconductive strips and indicator light 45. Preferably, the conductivestrips include at least one ground conductor 42 and at least one controlconductor 43 connected to bus 30. As will be described in greater detailbelow, tray 40 provides a communication link between file folders 70,which are placed thereon to processor 20 whereby processor 20 can trackthe location of file folders 70 placed on file tray 40 and canselectively light indicator light 45 on tray 40 and any indicator light75 on file folders 70.

File cabinet 50 includes a plurality of drawers 54 a–54 c, each of whichincludes an indicator light 55 a–55 c on an outer drawer face. Eachdrawer 54 a–54 c further includes a bus conductor 80 having at least oneground conductor 52 and a control conductor 53, which contact theconductive strips of file folders 70, and addressable drawer switch 100(FIG. 4), which is connected between ground conductor 52, controlconductor 53, and indicator light 55 a–55 c. File cabinet 50 mayoptionally include a branch indicator 95 (FIG. 3) associated with abranch control point 92 (FIG. 2) and having a unique cabinet address andan indicator light 51 that can be lit whenever processor 20 transmits acontrol signal including the unique cabinet address of the addressablecabinet switch.

Shelving unit 60 includes at least one shelf 61 a–61 b, which includes abus conductor 80 having at least one ground conductor 62 and a controlconductor 63 for contacting the conductive strips of file folders 70.Shelving unit 60 also preferably includes an addressable switch 100having a unique address and an indicator light 65, which can be litwhenever processor 20 transmits a control signal including the uniqueaddress of the addressable switch.

Desk 85 includes at least one drawer 86 a, 86 b which includes a busconductor 80 therein and an indicator 87 a, 87 b on an outer facethereof. In addition, desk 85 may include a bus conductor 80 embedded ina work surface thereof. Further, a mat 88 having a bus conductor 80embedded therein may be placed on the top of desk 85 or any otherworking surface of an article of furniture.

FIG. 2 illustrates a typical system hierarchy employed when severalbranch connections exist in the system. A user's work area 90 mayinclude, for example, a processor 20 and a plurality of file cabinets50. Because each file cabinet 50 includes a plurality of drawers 54 a–54c, which, in turn, contain a plurality of file folders 70, file trackingsystem 10 preferably utilizes the hierarchy shown in FIG. 2 toseparately activate a single branch at a time. To enable a single branchto be activated at a time, file tracking system 10 preferably includes aplurality of branch control points 92,92′, which may be individuallyactivated to permit access to the branch controlled by the branchcontrol point 92. Thus, to access file folders 70 in a drawer 54 a offile cabinet 50 a, processor 20 transmits a control signal to the branchcontrol point 92 for the file cabinet 50 a such that processor 20 maynot transmit a control signal to the branch control point 92′ for drawer54 a. After processor 20 transmits a control signal to branch controlpoint 92 for cabinet 50 a, processor 20 transmits a control signal tothe branch control point 92′ for drawer 54 a to activate the busconductors 80 located in drawer 54 a thereby allowing processor 20 tocommunicate with file folders 70 included in file drawer 54 a.Alternatively, a processor 20 that is located outside user's work area90 may access file folders 70 within user's work area 90 by transmittingcontrol signals through a network 91. File tracking system 10 mayfurther include a serial port adaptor or secondary processor 27, whichis connected to receive control signals from a serial port of processor20, convert the received control signals to a format appropriate for asingle pair bus, and distribute the control signals to the correct filecabinet 50 or other folder retainer connected to the system.

FIG. 3 shows an exemplary electrical schematic of the connectionsbetween processor 20 and file folders 70. As shown in FIG. 3, bus 30includes a control line 31 and a ground line 32. Bus 30 is preferably asingle pair bus. In the hierarchical arrangement shown in FIG. 3, branchcontrol point switch assemblies 93 a and 93 b represent control pointsfor activating the bus conductors 80 of two different file drawers 54 ofa file cabinet 50. Although only one file folder (70 a, 70 b) is shownfor each file drawer 54, each file drawer 54 will typically have aplurality of file folders 70 contacting its bus connector 80.

Each file folder 70 preferably includes a folder indicator light 75 andan addressable folder switch 76 having a unique address associatedtherewith. Alternatively, each folder may include an addressable devicewhen an indicator is not employed such that each folder has a unique IDtag that may be communicated to processor 20. Although the file folders70 are illustrated as bi-fold file folders, as stated above, the filefolders may be any type of file folder as previously defined.

FIG. 4 shows the general structure of an addressable switch 100 usefulin the file tracking system of the present invention. Addressable switch100 includes a load transistor 101 having a gate 102, a source servingas a load terminal 103, and a drain serving as a ground terminal 104.Addressable switch 100 further includes a digital control device 105connected between gate 102 and a control terminal 106. Digital controldevice 105 includes a read only memory (ROM) 108 in which the uniqueaddress of addressable switch 100 is stored.

Digital control device 105 receives control signals at control terminal106. These control signals include an address and a command. Whendigital control device 105 senses a control signal at control terminal106, digital control device 105 compares the address in the receivedcontrol signal to the unique address stored in ROM 108. If the addresscontained in the control signal is not the same as the unique addressstored in ROM 108, digital control device 105 awaits further controlsignals. If, on the other hand, the address contained in the controlsignal is the same as the unique address stored in ROM 108, digitalcontrol device 105 executes the command contained in the receivedcontrol signal or contained in a subsequently transmitted controlsignal.

In the context of the present invention, addressable switch 100 mayperform various tasks in response to an appropriate command received atcontrol terminal 106. For example, digital control device 105 may changethe state of load transistor 101 between conductive and nonconductivestates by controlling the voltage applied to gate 102. Additionally,digital control device 105 may transmit a reply signal over controlterminal 106 indicating the state of load transistor 101 or the uniqueaddress stored in ROM 108. By transmitting the state of load transistor101, digital control device 105 may transmit the status of an attachedindicator light. Preferably, digital control device 105 derives itspower entirely from control line 31 by storing energy in a capacitor (noshown) when control terminal 106 is in a high logic state. An example ofan addressable switch 100 that may be used in the file tracking systemof the present invention is the DS2405 addressable switch available fromDallas Semiconductor, in Dallas, Tex.

Referring again to FIG. 3, branch control points 92 a, 92 b, . . . 92 neach include at least one branch control point switch assembly 93 a, 93b, . . . 93 n including a branch control addressable switch 94 a, 94 b,. . . 94 n having a unique address associated therewith. Branch controlpoint 92 a may also include a branch indicator 95 a, which includes abranch indicator light 96 a, such as an LED, and a branch indicatoraddressable switch 97 a having a unique address associated therewith topermit independent control of branch indicator light 96 a by processor20.

To communicate with file folder 70 a located in a particular drawer 54a, processor 20 transmits a control signal over control line 31 viaserial port adaptor 27 to control terminals 106 of all branch controladdressable switches 94 a, 94 b, . . . 94 n connected to ground line 32.The transmitted control signal includes the unique address associatedwith branch control addressable switch 94 a associated with drawer 54 awith which communication is desired. The control signal also includes acommand instructing this branch control addressable switch 94 a tochange to a conductive state thereby providing a connection betweenground line 32 and addressable folder switch 76 a. Subsequently,processor 20 may transmit control signals individually to addressablefolder switch 76 a by including the unique address associated therewith.Thus, processor 20 may illuminate folder indicator light 75 a of anyspecified file folder within a specified drawer 54 a. Additionally,processor 20 may obtain information from addressable folder switches 76a, 76 b, . . . 76 n through a later described, deterministic process todetermine the unique address stored in ROM 108 of each of addressablefolder switches 76 a, 76 b, . . . 76 n. Processor 20 may also illuminatebranch indicator light 96 a by first transmitting a control signalincluding the unique address of branch control addressable switch 94 aand subsequently transmitting a control signal including the uniqueaddress of branch indicator addressable switch 97 a. By providing abranch indicator light 96 a on a folder retainer such as a file drawer54 a, a file tray 40, or a shelving unit 60, one can quickly determinein which folder retainer a selected file folder 70 is located by lookingfor the folder retainer with the illuminated branch indicator light 96.

In the preferred embodiment, each file folder 70 has an addressableswitch having a unique address associated therewith in any given systeminstallation. In some applications, multiple file folders 70 couldintentionally have identical addresses corresponding to files related orgrouped in some fashion. Further, an inadvertent duplication ofaddresses could result in any installation from a finite number ofaddresses in a mass produced, manufacturing environment. In all suchsituations, unique addresses are still present as envisioned herein.

The manner in which contact can be made between the conductive strips ona file folder 70 and the conductive rails of a bus conductor 80 will nowbe described with reference to FIGS. 5–7.

Bus conductors 80 a, 80 b, 80 c preferably include at least one groundconductive rail 82 a, 82 b, 82 c, a control conductive rail 83 a, 83 b,83 c, and a support 84 a, 84 b, 84 c for supporting the conductiverails. Support 84 a, 84 b, 84 c preferably is formed of an electricallyinsulating material and supports the conductive rails in parallel withone another. Bus conductor 80 a–80 c may be formed as an integral partof a folder retainer or, alternatively, may be formed as a separateelement which may be added to an existing folder retainer. As shown inFIG. 5, bus conductors 80 a may be implemented in a vertically spaced,horizontally extending manner to provide contact along a vertical side,end, or back surface of a folder retainer. Thus, using bus conductor 80a, contact may be provided along the back of a shelving unit or bookcaseor along the side of a file or desk drawer. Alternatively, as shown inFIG. 6, bus conductor 80 b may be implemented such that contact isprovided in a horizontally spaced, horizontally extending manner along ahorizontal or bottom surface of a folder retainer. Horizontallyextending bus conductor 80 b is advantageous in that contact with thefile folders is aided by gravitational forces and that contact may bemade with either the edges of file folders vertically stacked thereon orwith the large exterior surfaces of file folders laid flat thereon.Moreover, as shown in FIG. 7, bus conductor 80 c may be implemented as asupport rail in a file drawer 54 upon which hanging file folders 70 cmay be suspended. In such an implementation, file folder 70 c does notrequire conductive strips, but rather a file folder indicator lightassembly 71 is provided having a contact 78 for contacting controlconductive rail 83 c and a wire 77 connected to file folder hangerextension 74, which in turn contacts ground conductive rail 82 c.However, hanging file folders 70 c may still have such conductive stripsto provide stackability and redundant contact through adjacent filefolders as is later described.

Bus conductors 80 may optionally be disposed in more than one surfaceand in various combinations. For example, one conductive rail may bedisposed on the bottom interior surface of a file drawer, while anotherconductive rail may be disposed on an interior side surface of the filedrawer. Further, one conductive rail may be disposed on the side orbottom of a file drawer and another conductive rail may be disposed on asupport rail, such as that shown in FIG. 7. Additionally, in a shelf orbookcase, one conductive rail could be disposed on a back surface andanother could be disposed on a top surface of a shelf.

File folders 70 a, 70 b preferably include conductive strips includingat least one return conductive strip 72 a, 72 b and a control conductivestrip 73 a, 73 b arranged in a pattern that allows for relative movementbetween file folders or between the file folder and a bus conductor,such as that shown in FIG. 5 or that shown in FIG. 6. The conductivestrips are preferably applied to both large exterior surfaces as well asmade to extend around the side and bottom edges. By applying theconductive strip pattern to both large exterior surfaces of file folder70 a, 70 b, 70 c, a file folder 70 a, 70 b, 70 c that is not in directcontact with bus conductor 80 a, 80 b is nevertheless permitted to havea connection to bus conductor 80 a, 80 b via adjacent and intermediatefile folders 70 a, 70 b, 70 c. Thus, if too many file folders 70 a, 70b, 70 c are placed in a file drawer 54 such that a file folder 70 a, 70b, 70 c is laterally shifted and cannot directly contact bus conductor80 a, 80 b a connection will be provided through adjacent file folders70 a, 70 b, 70 c. Similarly, file folders 70 a, 70 b, 70 c stacked in afile tray 40 will have a connection to bus conductor 80 a, 80 b via filefolders 70 a, 70 b, 70 c positioned therebetween.

As shown in FIG. 5, file folder 70 a has at least one large exteriorsurface having a top and bottom edge as well as left and right sideedges. The conductive strip pattern shown thereon includes threeconductive strips (i.e., conductors)—one control conductive strip 73 aand two return conductive strips 72 a. The control conductor 73 a is “V”shaped and includes a first conductive linear strip 73 a′ extending fromthe left edge of the surface to a central point on the bottom edge ofthe surface and a second conductive linear strip 73 a″ extending fromthe central point on the bottom edge of the surface to the right edge ofthe surface. A first one of the return conductors 72 a includes a linearstrip 72 a′ extending in parallel to the first conductive linear strip73 a′ of the control conductor 73 a from the left edge of the surface tothe bottom edge of the surface. The other one of the return conductors72 a includes a linear strip 72 a″ extending in parallel to the secondconductive linear strip 73 a″ of the control conductor 73 a from thebottom edge of the surface to the right edge of the surface. The linearstrips of the two return conductors 72 a are positioned an equaldistance on opposite sides of the control conductor 73 a. Preferably,the same conductive strip pattern is applied to the back or otherexterior surfaces of file folder 70 a.

As shown in FIG. 6, file folder 70 b also has at least one largeexterior surface having a top and bottom edge as well as left and rightside edges. The conductive strip pattern shown thereon includes threeconductive strips—one control conductive strip 73 b and two returnconductive strips 72 b. The control conductor 73 b consists of aconductive linear strip extending from the top edge of the surface to abottom edge. The return conductors 72 b are formed of two linear strips72 b′ and 72 b″, each extending in parallel to the conductor linearstrip of the control conductor 73 b from the top edge to the bottomedge. The two linear strips 72 b′,72 b″ constituting the returnconductors 72 b are positioned an equal distance on opposite sides ofthe control conductor 73 b. Preferably, the same conductive strippattern is applied to the back or other exterior surfaces of file folder70 b.

The conductive strip patterns shown in FIGS. 5 and 6 permit properelectrical contact even when the file folders 70 a, 70 b are rotated180° about the illustrated y axis, which parallels the left side edgesof the file folders, relative to one or more adjacent file folders orrelative to bus conductor 80 a, 80 b. The conductive strip pattern shownin FIG. 5 may be utilized with either of the bus conductors 80 a, 80 bshown in FIGS. 5 and 6 because the strips overlap or extend around boththe bottom and side edges of the file folder and permit properelectrical contact even when a file folder 70 a is rotated 90° about thez axis, which is orthogonal to the large exterior surfaces of filefolders 70 a, 70 b, with respect to adjacent file folders or busconductor 80 a, 80 b. Further, the conductive strip pattern shown inFIG. 5 permits contact when laid flat on an adjacent file folder or anappropriately arranged bus conductor.

The conductive strip pattern shown in FIG. 6 is similarly advantageousin that proper electric contact may be made regardless of whethercontact is made with the edge of file folder 70 b or with the entiresurface of file folder 70 b should file folder 70 b be laid flat onconductive bus 80 b. Thus, with respect to bus conductor 80 b or anadjacent file folder, file folder 70 b may be rotated 180° about the x,y, and z axes, and further may be rotated 90° about the x axis, whichparallels the bottom edges of file folders 70 a, 70 b, withoutdisrupting the electrical contact between bus conductor 80 b and theconductive strips. Additionally, the conductive strip pattern shown onfile folder 70 b permits file folders 70 b to be significantly laterallyshifted in the y direction relative to one another while stillmaintaining the necessary contact.

Hence, the conductive strip patterns are configured to electricallyconnect an addressable folder switch 76 with electrical contacts of thefile tracking system when the file folder is positioned in any one ofseveral different positions that allow a proper connection to be made.Further, the conductive strip patterns are configured to electricallyconnect an addressable folder switch 76 with the file tracking systemwhen the file folder 70 is positioned in (1) any one of severaldifferent orientations with respect to the electrical contacts of theelectronic file tracking system; (2) any one of several differentlateral positions with respect to an adjacent file folder; or (3) anyone of several different rotated positions with respect to an adjacentfile folder. Additionally, the conductive strip pattern is preferablyconfigured to electrically connect the addressable folder switch 76 tothe file tracking system at a plurality of locations on the file folder70.

The conductive strips may be formed of conductive tape, fabric, coating,which may be a conductive ink or polymer, or other suitable conductivematerials. The choice between such materials being a factor of the shapeand composition of the particular file folder, cost and longevity goals,and other concerns.

As evident from the foregoing description of the bus conductors and theconductive strip patterns applied to the file folders, the file trackingsystem of the present invention offers exceptional flexibility, both indesign and in use.

Having described the preferred structure of the first embodiment of thepresent invention, the operation of file tracking system 10 will now bedescribed with reference to FIGS. 8–13.

FIG. 8 shows a main user interface window 200 that a user would see ondisplay 22 of processor 20. Main user interface window 200 indicates thetitle 201 of a file identified in the database, the content and keywordsof the file 202, the location of the file 203, the originator of thefile 204, the date the file was filed in the system 205, the name of thelast user of the file 206, the date the file was last removed from thesystem 207, and the date the file was returned to the system 208. Thedatabase may store additional information for display to the user. Forexample, the database may store the locations in a computer networkwhere any redundant copies of the file are stored.

The software utilized in file tracking system 10 generally includes auser interface module for providing windows, dialog boxes, and menus,such as window 200. Preferably, the user interface module operates in agraphic user interface such as Windows® software available fromMicrosoft Corporation. The software also includes several standaloneevent subroutines that are executed when their associated controls areactivated by a user or for timed events, at the configured intervals.The event subroutines may be classified into four main functionalgroups: a database interface; a bus interface; option control; and Debugcontrol.

The database interface subroutines provide the viewing, editing, andsearch capability for the file folder records. The viewing controlsallow movement through the database records and the display of recordfields. The editing controls allow the entry, deletion, and updating ofdatabase records. The search controls let the user locate records byvalue within the title or content\keyword field, and the viewing of thesearched group.

The bus interface subroutines compile and issue control signals over bus30 to the various branch control point switch assemblies 93 and filefolders 70 on the system. An example of an interface for a single pairbus having addressable switches 100 connected thereto is TMEX™ interfaceavailable from Dallas Semiconductor, Dallas, Tex. Preferably, the businterface includes functions to start and stop a communication session,identify attached devices, and sense and control the functioning of theaddressable switches.

The option control subroutines allow the user to adjust the indicatorlight blink rate, the indicator light ON duration, bus scan rate, devicepersistence, and form display to include debug information. A user mayset the indicator light blink rate and the bus scan rate by defining theperiod between their events, which is the interval property of theirtimer control. The user may set the device persistence in increments ofbus scan rate and controls the length of time that passes beforeprocessor 20 considers a missing file folder device to be removed. Thispersistence compensates for intermittent contacts during file foldermovement. The debug information includes a status window used to displayprogram messages, access to debug controls, and database fields notnormally of interest to the user such as state variables and the uniqueaddress associated with the device.

The debug controls allow the status messages to be cleared, the bus tobe reset, and the scan timers to be enabled/disabled. FIG. 9 shows adebug window 210 illustrating the manner in which the user interfacepresents the debug controls to a user.

The operations described below, utilize various combinations of theevent subroutines described above. Thus, any given operation may includeone or more data interface subroutine, bus interface subroutine, optioncontrol subroutine, and/or debug control subroutine.

FIG. 10 shows a polling rate request window 215, which allows a user toadjust the rate at which file tracking system 10 polls the file folderslocated within the system. A user may display the polling rate requestwindow 215 by selecting the “Options” menu on main user interface window200.

With the exception of the ability to adjust the polling rate, processor20 generally polls file folders 70 and maintains the databasetransparently to the users. The manner by which processor 20periodically polls file folders 70 will be described with reference tothe flow charts shown in FIGS. 11 and 12.

Polling (Step 300) occurs periodically at the rate established by theuser in polling rate request window 215. Initially, processor 20executes a scan of a main branch looking for new, reconnected, andremoved branch control point switch assemblies 93 (Step 302). The mannerby which processor 20 performs this operation is shown in the flow chartin FIG. 12.

Processor 20 initiates a scan 302, 330 by opening communication with thedesired main branch 98 (FIG. 2) (Step 304). Then processor 20 attemptsto detect the presence of a device (in this case a branch controlleraddressable switch) (Step 306). By a process of elimination, processor20 may determine the unique address of any newly detected branchcontroller addressable switch 94 and store the unique address in thedatabase. If a branch controller addressable switch 94 is found,processor 20 queries whether branch controller addressable switch 94 isnew by accessing the database and determining whether a branchcontroller addressable switch 94 having the received unique address waspreviously registered therein (Step 308). If the branch controlleraddressable switch 94 detected is new, processor 20 adds the branchcontroller addressable switch 94 to the database and automatically fillsin whatever fields can be filled in with the information that may beobtained such as the location of branch controller addressable switch 94(Step 310).

To determine the unique address of devices, such as addressable folderswitches 76 and branch controller addressable switches 94, located on agiven branch, processor 20 issues a command instructing the addressablefolder switches 76 and branch controller addressable switches 94 totransmit the unique address stored in ROM 108 bit by bit. When aplurality of devices are present on the activated branch, each of themsimultaneously transmits the first bit of the unique address on bus 30.Processor 20 senses the state of bus 30, which represents a logical ANDof all the first bits of each device located on the activated bus.Processor 20 then issues a command to each device to transmit thecomplement of the first bit of their respective unique address. Ifprocessor 20 detects two “0's” in response to these two inquiries,processor 20 determines that there are devices located on the branchthat have a “0” in the first bit position and other devices having a “1”in the first bit position. If all devices had a “0” in the first bitposition, the reading would have been a “0” followed by a “1”. If a “1”followed by a “0” were received, processor 20 determines that all thepresent devices have a “1” in the first bit position. Last, if processor20 detects two “1's”, no devices are present on the activated branch.

The above procedure for identifying unknown devices on a branch may befurther optimized by first disabling all known devices on the branch andthen performing the operation on those devices that are not disabled. Inthe illustrated embodiment, such procedure is carried out using theSearchROM command included with the TMEX Software from DallasSemiconductor.

Processor 20 then issues a control signal including one of the “1” or“0” logic values in the first bit position in order to disable thedevices that do not have this logic value in the first bit position oftheir unique address. Processor 20 then issues a command to the devicesthat remain enabled requesting these devices to transmit the second bitof their unique addresses and the complement thereof. Processor 20 thenuses the same process to determine the value of the second bit of atleast one of the remaining devices. Processor 20 repeats the above stepsuntil the unique address of one of the devices is known.

Subsequently, processor 20 reactivates the other devices on theactivated branch and repeats the above process using a different logiclevel at the highest bit position where processor 20 was able todetermine that a single device remained. In this manner, processor 20determines the unique address of each file folder 70 and branchcontroller 93 located on an activated branch.

After the new branch controller addressable switch 94 has been added tothe database, processor 20 scans the rest of main branch 98 looking foradditional branch controller addressable switches 94 (Step 306). Ifprocessor 20 detects a branch controller addressable switch 94 on themain branch 98 that is not new, processor 20 compares the branchcontroller state and location with that previously stored in thedatabase and updates the database if any changes are detected (Step312). Processor 20 continues to search for additional branch controlleraddressable switches 94 on main branch 98 until no further branchcontroller addressable switches 94 are detected in Step 306.

When processor 20 determines that no further branch controlleraddressable switches 94 are present on main branch 98, processor 20closes communication with main branch 98 (Step 314). Next, processor 20queries the database for the number of branch controller addressableswitches 94 presently registered in the database as being located onmain branch 98 (Step 315) and compares this number with the number ofbranch controller addressable switches 94 that processor 20 detected inStep 306 while scanning main branch 98 (Step 316). If the number ofbranch controller addressable switches 94 presently registered exceedsthe number of branch controller addressable switches 94 detected,processor 20 determines that at least one branch controller addressableswitch 94 has been removed from main branch 98.

To verify that a branch controller addressable switch 94 has beenremoved, processor 20 reopens communication with main branch 98 (Step318) and transmits control signals to each branch controller addressableswitch 94 registered in the database by including the unique addressthereof in the control signal, which is stored in the database (Step320). If a branch controller addressable switch 94 fails to respond tothe control signal sent by processor 20, processor 20 changes the stateof the branch controller addressable switch 94 registered in thedatabase to “timing out” (Step 322). After processor 20 transmits acontrol signal to each registered branch controller addressable switch94, processor 20 closes communication with main branch 98 (Step 324).

After processor 20 has closed communication with the reopened mainbranch 98 in Step 324 or after processor 20 has determined that thenumber of branch controller addressable switches 94 registered in thedatabase does not exceed the number of branch controller addressableswitches 94 detected in Step 316, processor 20 queries the database forthe identity and unique address of all present branch controlleraddressable switches 94 on the main branch 98 (Step 326 in FIG. 11) andchanges the state of addressable branch controller switches 94 toconducting one at a time in order to activate each secondary branch 99(Step 328).

While a branch controller addressable switch 94 is conducting, processor20 scans the activated branch for new, replaced, or removed file folders70 contacting the activated branch (Step 330). The manner by whichprocessor 20 performs this operation is shown in the flow chart in FIG.12.

First, processor 20 opens communication with the desired secondarybranch 99 (Step 304). Then processor 20 attempts to detect the presenceof a device (in this case a file folder 70) (Step 306). If a file folder70 is found, processor 20 queries whether file folder 70 is new byaccessing the database and determining whether file folder 70 waspreviously registered therein (Step 308). If the file folder 70 detectedis new, processor 20 adds file folder 70 to the database andautomatically fills in whatever fields can be filled in with theinformation that may be obtained (Step 310). By the process ofelimination, processor 20 may determine the unique address of any newlydetected addressable file folder switch 76 and store the unique addressin the database. After the new file folder 70 has been added to thedatabase, processor 20 scans the rest of the opened secondary branch 99looking for additional file folders 70 (Step 306).

If processor 20 detects a file folder 70 on the opened secondary branch99 that is not new, processor 20 compares the file folder state andlocation with that previously stored in the database and updates thedatabase if any changes are detected (Step 312). Processor 20 continuesto search for additional file folders 70 on secondary branch 99 until nofurther file folders 70 are detected in Step 306.

When processor 20 determines that no further file folders 70 are presenton the opened secondary branch 99, processor 20 closes communicationwith this secondary branch 99 (Step 314). Next, processor 20 queries thedatabase for the number of file folders 70 presently registered in thedatabase as being located on this secondary branch 99 and compares thisnumber with the number of file folders 70 that processor 20 detected inStep 306 while scanning the secondary branch 99 (Step 316). If thenumber of file folders 70 presently registered exceeds the number offile folders 70 detected, processor 20 determines that at least one filefolder 70 has been removed from the opened secondary branch 99.

To verify that a file folder 70 has been removed, processor 20 reopenscommunication with the secondary branch 99 (Step 318) and transmitscontrol signals to each file folder 70 registered in the database byincluding the unique address thereof in the control signal, which isstored in the database (Step 320). If a file folder 70 fails to respondto the control signal sent by processor 20, processor 20 changes thestate of the file folder 70 registered in the database to “timing out”(Step 322). After processor 20 transmits a control signal to eachregistered file folder 70, processor 20 closes communication with thissecondary branch 99 (Step 324).

After processor 20 has closed communication with the reopened secondarybranch 99 in Step 324 or after processor 20 has determined that thenumber of file folders 70 registered in the database does not exceed thenumber of file folders 70 detected in Step 316, processor 20 activatesanother secondary branch 99 by transmitting a control signal includingthe unique address of the branch controller addressable switch 94associated with the selected secondary branch 99 (Step 328 in FIG. 11).

After processor 20 has scanned all the secondary branches 99, processor20 queries the database for the identity of all devices in the “timingout” state (Step 332) and decrements the persistence values stored inassociation therewith (Step 334). The persistence value indicates thenumber of additional times that processor 20 will perform a scan of allfile folders 70 before a file folder having a “timing out” status willbe considered to have a “timed out” or removed status. When a filefolder has “timed out” (Step 336), processor 20 updates the database toindicate this change in status (Step 338) and ends the scanningoperation (Step 340). Once the scanning operation is finished, a timeris started to determine when the next scanning operation is to beperformed.

Processor 20 automatically updates the database by inserting the dateand time the file was detected as having been removed from the systeminto the appropriate database fields associated with file folder 70.Additionally, processor 20 may identify the individual who removed filefolder 70 by determining who was the last individual to log onto thesystem and cause the indicator light of the removed file folder toblink. This is especially helpful in locations where security measuresrequire logging onto the system before removing files. Then, if thepresence of the removed file folder 70 is subsequently detected at adifferent location, such as on an individual's desk, processor 20 mayupdate the database to indicate that the individual who removed the fileis the individual associated with the location (i.e., desk) where filefolder 70 was subsequently detected or have a separate fieldcorresponding to the individual responsible for that particular area orlocation.

By actively polling each file folder 70, file tracking system 10maintains an accurate record of file folder location and usage historywithout requiring action by office personnel. Moreover, office personnelneed not spend their valuable time keeping the files organized. Usingfile tracking system 10, a person may quickly determine the presentlocation of a file folder and cause LEDs on the file folder and filecabinet drawer to blink to allow the person to quickly identify therequested file folder. Because of the ease by which a person may locatea file folder, office personnel may place the file folders anywhere andin any convenient order. Thus, office personnel may place the mostfrequently used file folders at the front of a file drawer where theyare more easily accessed at a later time. Furthermore, because new filefolders may be placed in any file drawer or on any shelf, there is noneed to rearrange the file folders to make room for new file folders.

In addition, by utilizing a database to index file folders, the filefolders may be physically grouped or classified into various topicalgroups and subgroups. Thus, a user may access all the file foldersconstituting the group or subgroup. Moreover, by issuing an appropriatecommand, a user can cause the indicator lights on all the file foldersof a selected group of file folders to blink thereby adding to the easeby which the user can locate the physical file copies for immediate useor to gather for placement into a desired storage pattern or location.Similarly, a user can locate all files mentioning a particular subjectby performing a keyword search. Thus, the present invention may providehigher levels of file organization even if a user wishes to maintain thefiles in a specific nonrandom order.

FIG. 13 is a flow chart illustrating the operation of file trackingsystem 10 when operating in an indicator light scanning operation. Aswill be apparent from the following description, the indicator lightscanning operation is useful for causing the indicator lights on theselected file folders and branch indicators to blink.

An indicator light scanning operation is performed at timed intervals(Step 400). Processor 20 begins the operation by querying the databasefor all present branch controller addressable switches 94 on the mainbranch (Step 402). Then, for each branch controller addressable switch94 that is present (Step 404), processor 20 queries the database forfile folders 70 having an indicator light blink flag set to logic “1”and located on the branch controlled by the selected branch controlleraddressable switch 94 (Switch 406). The indicator light blink flag for afile folder is set when a user requests processor 20 to blink theindicator light of a selected file folder. If no file folders are foundthat are connected to the selected branch (Step 408) and have theirindicator light blink flag set to “1”, processor 20 selects the nextbranch (Step 404). If the processor 20 finds file folders 70, processor20 queries the database for branch indicators on the selected branch(Step 410), then processor 20 opens communication with the selectedbranch (Step 412) and transmits control signals to each branch indicator95 that is found on the selected branch (Step 414) causing the branchindicator lights 96 to toggle on and off (Step 416). Next, processor 20transmits control signals to each file folder 70 that is found on theselected branch having its indicator light blink flag set to “1” (Step418) causing the folder indicator lights 75 to toggle on and off (Step420). After all of the folder indicator lights 75 on the selected branchhave been toggled, processor 20 closes the selected branch (Step 422)and selects the next branch (Step 404). The process is repeated untilthere are no more branches to select (Step 424). This procedure may beprogrammed to be executed several times per second.

The control signals transmitted by processor 20 to toggle the indicatorlights may include a first control signal containing the unique addressof the addressable device followed by a second transmitted controlsignal including a command to toggle the indicator light. Alternatively,the control signals may include a single control transmitted byprocessor 20 that includes both the unique address and the command totoggle the indicator light.

Although the above procedure is presently used to blink the indicatorlights, it is also possible to utilize indicator lights that blink uponreceiving an instruction to do so until a subsequent instruction isreceived to stop blinking. Further, processor 20 may read each indicatorfor the status of the indicator light prior to issuing a control signalcausing the indicator light to blink in order to ensure that theindicator light is not already turned on.

FIG. 14 shows a file tracking system 500 constructed in accordance witha second embodiment of the present invention.

The second embodiment of the file tracking system 500 differs from thefirst embodiment only in that file tracking system 500 includes aplurality of processor 20 a–20 d interconnected by a network, such as alocal area network (LAN) 91 or a local office network (LON). An exampleof a LON in which the present invention may be implemented is disclosedin U.S. patent application Ser. No. 08/165,029, the disclosure of whichis incorporated by reference herein. Each processor may store a portionof the entire database of the system such that the various processorsand their respective portions of the database constitute a distributeddatabase system 501. In such a system any one of processors 20 a–d mayaccess the database stored in any other processor using a conventionaldistributed database management system (DDBMS), a networked databaseserver, or through database information stored with the file folder.

The DDBMS architecture of tracking system 500 allows any single filetracking program to operate on records that are spread across multipledatabases that are running on a variety of different processors andoperating systems connected through a variety of communication networks.In a networked database server, a single processor maintains a centraldatabase with the other processors having a subset copy of the recordspertaining to the file folders local to each processor. A processorwould use this local copy to monitor the file folder state and indicatorlight state, and relay only changes in state back to the centraldatabase.

By scaling the file tracking system of the present invention to permitmultiple access to the system at various locations, file tracking system500 permits multiple users in various locations to locate file foldersthat are in distributed locations about the organization. Thus, thissystem can easily be adapted for use in a large organization havingnumerous office buildings in which file folders may be located in anyoffice or file repository of these office buildings.

Although the above embodiments of the present invention have beendescribed as using physical connections between the various elements,any one or all of the above connections may be replaced with a radiolink by providing a radio frequency (RF) transceiver connected toprocessor 20 and RF transceivers on the folder retainers and/or the filefolders themselves. FIG. 15 shows a third embodiment using RF signals.The third embodiment differs from the second embodiment in that RFtransceivers 120 are connected to processor 20 and either to each filefolder 70 or to each folder retainer, which refers to tray 40, filecabinet 50, shelving unit 60, and desk drawer 86. The third embodimentmay utilize the same RF communication protocols as used in cellulartelephones. For example, the system may employ cellular digital packetprotocol (CDPP) or the protocol used for personal communication systems(PCS). These protocols may be employed by utilizing branch controllersas a cell base station whereby file folders located within each cellregister with the closest cell base station such that processor 20 maytrack the location of each file folder.

Although the embodiment shown illustrates a system utilizing all RFlinks from processor 20, a combination of RF links and physical busconnections may also be employed. By providing the availability of radiolinks, mobile folder retainers, such as file carts, as well as remotelylocated folder retainers may be employed in the file tracking system ofthe present invention.

Although the processor(s) of the present invention have been describedwith reference to personal computers, the processor may be a processorembedded in or near the folder retainer. In such an arrangement, it maybe preferable for the embedded processor to include a plurality ofserial ports to which different branches of the bus may be connected,thus, eliminating the need for a number of branch controllers. Further,the processors may be computer terminals connected to a network.

Further, processor 20 may be implemented in either a single processingunit or in a distributed system whereby various tasks performed byprocessor 20 are allocated to various components of the distributedsystem. For example, one component may be responsible for scanning thebus, while another may be used to provide an interface with the users.Further, various tasks described above as being performed by processor20 may be allocated to embedded processor 27. For example, embeddedprocessor 27 may maintain separate databases identifying which filefolders are located on their associated branch.

Additionally, other types of annunciators or, as more broadly definedherein, file locating devices, such as an audible alarm, may supplementor replace the visual indicator lights used in the file tracking system.

Although it is preferable that the present invention be practiced usingaddressable devices that each have unique addresses associatedtherewith, it is possible that in a system employing a large number ofaddressable devices, two or more addressable devices could have the sameaddress. The present claims are intended to cover the situation where atleast a plurality of addressable devices have unique addresses. Toensure such coverage, some claims below recite that the addressabledevices have a substantially unique address.

The foregoing description of preferred embodiments of the invention hasbeen presented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed, and modifications and variations are possible in light of theabove teachings or may be acquired from practice of the invention. Theembodiments were chosen and described in order to explain the principlesof the invention and its practical application to enable one skilled inthe art to utilize the invention in various embodiments and with variousmodifications as are suited to the particular use contemplated. It isintended that the scope of the invention be defined by the claimsappended hereto, and their equivalents.

1. A file tracking system comprising: a database for maintaining filelocation and unique file addresses for a plurality of files; a processorfor interfacing with said database and issuing control signals; a busconnected to said processor; a folder retainer connected to saidprocessor by said bus; and a plurality of file folders, each file folderincluding an addressable device adapted to be electrically connected tosaid bus when the file folder is placed in said folder retainer, eachaddressable device being responsive to a control signal including theunique address associated with the addressable device to transmit asignal back to said processor so that said processor may maintain thefile location of each file in said database.
 2. The file tracking systemof claim 1, further including an indicator located on one of said filefolders, wherein said addressable device includes an addressable switchand said indicator is activated when said addressable switch receives acontrol signal from said processor including the unique addresscorresponding to the file folder.
 3. The file tracking system of claim2, further including: an input device for receiving commands and fileidentification information from an operator and providing the commandsand file identification information to said processor, wherein, when theoperator inputs a command to search for a specific file, said processoraccesses a unique address and file location stored in said database ascorresponding to input file identification information identifying thespecific file to be searched for, displays the file location, andtransmits a control signal including the unique address to theaddressable switch of the file folder containing the specific filecausing the addressable switch to activate the indicator.
 4. The filetracking system of claim 2, wherein said addressable switch includes: aROM having the unique file address stored therein; address comparingmeans for comparing an address included in a control signal receivedfrom said the processor with the unique address stored in said ROM; andstate changing means for changing the state of said addressable switchwhen said address comparing means determines that the address includedin the received control signal is the same as the unique address storedin said ROM.
 5. The file tracking system of claim 4, wherein saidaddressable switch further includes a load transistor having a gate, asource, and a drain, said gate connected to said state changing means,wherein said state changing means changes the state of said addressableswitch by turning on and off said load transistor.
 6. The file trackingsystem of claim 5, wherein said indicator is an indicator light having afirst terminal connected to said first conductor, and a second terminalconnected to said source of said load transistor, wherein said drain ofsaid load transistor is connected to said second conductor, and saidindicator light is turned on when said load transistor is turned on bysaid state changing means.
 7. The file tracking system of claim 1,wherein said processor includes: polling means for periodically pollingsaid file folders to determine the presence and location of each filefolder; means for updating said database when said polling meansdetermines that a file location is different from the locationpreviously stored or that a file that said database previously indicatedas present is no longer present.
 8. The file tracking system of claim 1,wherein said processor is a personal computer.
 9. The file trackingsystem of claim 1, wherein said processor is any one of a plurality ofcomputers connected to a local area network.
 10. The file trackingsystem of claim 9, wherein said database is a distributed databaseaccessible by any one of said plurality of computers.
 11. The filetracking system of claim 1, wherein each of said file folders furtherinclude: a surface; a first conductor on said surface for providingcontrol signals to said addressable device when the file folder isplaced in said folder retainer; and a second conductor on said surfacefor providing a ground to said addressable device.
 12. The file trackingsystem of claim 1, wherein said folder retainer includes: at least onesurface; a first conductive rail positioned on said surface forproviding power and control signals to the addressable devicespositioned on said plurality of file folders when said file folders areplaced in said folder retainer; and a second conductive rail positionedon said surface for providing a ground to the addressable devices whensaid plurality of file folders are placed in said folder retainer. 13.The file tracking system of claim 12, wherein at least one of said firstand second conductive rails are integrated into a suspension rail of afile drawer upon which hanging file folders may be suspended.
 14. Thefile tracking system of claim 12, wherein said folder retainer includesa plurality of shelves, and at least one of said first and secondconductive rails are located on at least one of said shelves.
 15. Thefile tracking system of claim 12, wherein said folder retainer is a filetray, wherein at least one of said first and second conductors arepositioned in said file tray.
 16. The file tracking system of claim 12,wherein said surface is an interior surface of a file drawer for use ina file cabinet, wherein at least one of said first and second conductiverails are positioned in said file drawer.
 17. The file tracking systemof claim 16, wherein at least one of said first and second conductiverails are positioned along a bottom of said file drawer.
 18. The filetracking system of claim 16, wherein at least one of said first andsecond conductors are positioned along a side of said file drawer.
 19. Afile tracking system comprising: a database for maintaining filelocation and unique file addresses for a plurality of files; a processorfor interfacing with said database and issuing control signals; a busconnected to said processor; an input device for receiving commands andfile identification information from an operator and providing thecommands and file identification information to said processor; aplurality of folder retainers each connected to said bus via anaddressable switch having a unique address, and each including anindicator for indicating the presence of a searched for file folder thatis located therein; and a plurality of file folders, each file folderincluding an addressable switch adapted to be electrically connected tosaid bus when the file folder is placed in said folder retainer, andeach including an indicator that is activated when said addressableswitch receives a control signal from said processor including theunique address corresponding to the file folder, wherein, when theoperator inputs a command to search for a specific file, said processoridentifies a first unique address and file location stored in saiddatabase as corresponding to input file identification informationidentifying the specific file to be searched for, displays the filelocation, identifies a second unique address in said database for theaddressable switch of the folder retainer in which the searched for filefolder is located, transmits a control signal that energizes a segmentof said bus within the folder retainer corresponding to the searched forfile, transmits a control signal including the second unique address tothe addressable switch of the folder retainer causing the indicator ofthe folder retainer to activate, and addressable switch of the filefolder containing the specific file causing the addressable switch toactivate the indicator located on the file folder.
 20. A file trackingsystem comprising: a database for maintaining file location and uniquefile folder address for a plurality of files, and a unique draweraddress of each file drawer in which the files are located; a processorfor interfacing with said database and issuing control signals; a busconnected to said processor; a plurality of file cabinets, connected tosaid processor by said bus, each of said file cabinets including aplurality of file drawers, each file drawer having: an outer face, anaddressable drawer indicator switch including a unique drawer address, adrawer indicator light connected to said addressable drawer indicatorswitch and located on said outer face the file drawer, a firstconductive rail connected to said bus for receiving control signals fromsaid processor, and a second conductive rail for providing a ground,wherein said addressable drawer indicator switch illuminates said drawerindicator light when said addressable drawer indicator switch receives acontrol signal from said processor including the unique drawer addresscorresponding to the file drawer; and a plurality of file folders, eachfile folder including an addressable folder indicator switch and afolder indicator light, wherein said addressable folder indicator switchis connected to said first and second conductive rails when the filefolder is placed in one of said file drawers, and said folder indicatorlight is illuminated when said addressable folder indicator switchreceives a control signal from said processor including the uniquefolder address corresponding to the file folder.
 21. The file trackingsystem of claim 20, wherein said database additionally maintains aunique cabinet address, and said file cabinets each further include anaddressable cabinet indicator switch connected to said bus and having aunique cabinet indicator address, and a cabinet indicator lightconnected to said addressable cabinet indicator switch, wherein saidaddressable cabinet indicator switch illuminates said cabinet indicatorlight when said addressable cabinet indicator switch receives a controlsignal from said processor including the unique cabinet indicatoraddress corresponding to the file cabinet.
 22. The file tracking systemof claim 20, wherein said first conductive rail provides power to saidaddressable folder indicator switches and said addressable drawerindicator switches.
 23. A method of locating a file comprising the stepsof: inputting information identifying the file to be located; accessinga database to determine a present location of the file, a uniqueidentification code associated with a receiver at the present locationof the file, and a unique identification code associated with the file;transmitting a first control signal to the receiver at the presentlocation of the file, the first control signal including the uniqueidentification code of the receiver, transmitting a second controlsignal to the file, the second control signal including the uniqueidentification code of the file; and activating an annunciator inresponse to receipt of one of the first and second control signals. 24.The method of claim 23, wherein the annunciator is located on the file.25. The method of claim 23, wherein the annunciator is located on thereceiver.
 26. The method of claim 23, wherein the annunciator is anindicator light.
 27. The method of claim 26, wherein said indicatorlight is located on the file and wherein the method further includes thestep of illuminating a second indicator light on the receiver inresponse to receipt of the first control signal at the receiver.
 28. Amethod of locating a file comprising the steps of: inputting informationidentifying the file to be located; accessing a database to determine apresent location of the file, a unique identification code associatedwith a folder retainer in which the file is located, and a uniqueidentification code associated with the file; transmitting a controlsignal to the file, the control signal including the uniqueidentification code of the file and the unique identification code ofthe folder retainer; and illuminating an indicator light on the file inresponse to receipt of the control signal at the file.
 29. The method ofclaim 28, further including the step of illuminating a second indicatorlight on the folder retainer in response to receipt of the controlsignal at the folder retainer.
 30. A file locating system comprising: adatabase for maintaining file location and unique file addresses for aplurality of files; a processor for interfacing with said database andissuing control signals; a bus connected to said processor; a folderretainer, connected to said processor by said bus; a plurality of filefolders, each file folder including an addressable switch connected tosaid bus when the file folder is placed in said folder retainer; a filelocating device adapted to aid in the location of a file folder inresponse to control signals issued by said controller; and a conductorprovided in said folder retainer and coupled to said bus, forestablishing a common communication path along which said controlsignals issued from said processor are transferred to the addressableswitches of at least two of said file folders.
 31. The file locatingsystem of claim 30, wherein said file locating device is an indicatorlight located on the file folder.
 32. The file locating system of claim30, further including: input means for inputting information identifyingthe file folder to be located, wherein said processor accesses saiddatabase to determine a present location of the identified file folder,a unique identification code associated with a folder retainer in whichthe file folder is presently located, and a unique identification codeassociated with the file folder, said processor transmits a controlsignal to the folder retainer in which the file folder is located, thecontrol signal including the unique identification code of the filefolder and the unique identification code of the folder retainer, andsaid file locating device includes an annunciator activatible inresponse to receipt of the control signal, said annunciator beinglocated on said folder retainer.
 33. The file locating system of claim32, wherein said annunciator is an indicator light.
 34. A file trackingsystem comprising: a processor for issuing control signals; a pluralityof folder retainers communicatively coupled to said processor, whereinat least one of said folder retainers is configured to support filefolders in an orientation different than that in which another folderretainer supports file folders; and a plurality of file folders, eachfile folder including an addressable device adapted to becommunicatively coupled to said processor when the file folder is placedin any one of said folder retainers.
 35. The file tracking system ofclaim 34, wherein said at least one folder retainer is configured tosupport hanging file folders.
 36. The file tracking system of claim 35,wherein said at least one folder retainer is a file cabinet drawer. 37.The file tracking system of claim 34, wherein said at least one folderretainer is configured to support file folders stacked vertically on topof one another.
 38. The file tracking system of claim 37, wherein saidat least one folder retainer is a file tray.
 39. The file trackingsystem of claim 34, wherein said at least one folder retainer isconfigured to support file folders that horizontally abut one another.40. The file tracking system of claim 39, wherein said at least onefolder retainer is a shelf.
 41. The file tracking system of claim 34,wherein at least one of said folder retainers is communicatively coupledto said processor by an RF link.
 42. The file tracking system of claim34, wherein at least one of said folder retainers is communicativelycoupled to said processor by a bus.
 43. A file tracking systemcomprising: a database for maintaining file identity, file location, andunique file addresses for a plurality of files; a processor forinterfacing with said database and issuing control signals; a busconnected to said processor; a plurality of folder retainers connectedto said processor by said bus, wherein at least one of said folderretainers is configured to support file folders in an orientationdifferent than that in which another folder retainer supports filefolders; and a plurality of file folders, each file folder including anaddressable device adapted to be electrically connected to said bus whenthe file folder is placed in any one of said folder retainers.
 44. Afile tracking system comprising: a processor for issuing controlsignals; a folder retainer having electrical contacts communicativelycoupled to said processor; and a plurality of file folders, each filefolder including an addressable device connected to conductive contactsprovided on an exterior surface of the file folder and adapted to beelectrically coupled to said contacts of said folder retainer, whereinsaid folder retainer is configured to support file folders that arestacked vertically upon one another such that each addressable device oneach file folder in a vertical stack supported by said folder retainer,is coupled to said electrical contents of said folder retainer throughthe conductive contacts provided on file folders therebelow.